NEW YORK (Reuters Health) - A new approach to prophylactic vaccination of infants born to mothers with hepatitis B virus infection is improving outcomes, Swedish investigators say.

Dr. Bj�rn Fischler told Reuters Health by email "The results of the previous vaccination program for newborns to hepatitis B infected mothers in Stockholm County were unsatisfactory. In this new vaccination program, significant improvements were seen in the number of children adequately vaccinated and followed up, thereby reducing the risk of new chronic infections with the virus."

Dr. Fischler of Karolinska University Hospital, Stockholm and colleagues say that in 2000 and 2001, 227 children were born to mothers with known chronic hepatitis B. Only 63% of the 227 children had been adequately followed up with hepatitis B serology after completed vaccination.

Furthermore, between 1999 and 2003, chronic hepatitis B was diagnosed in two young children who had presumably not been vaccinated according to recommended guidelines.

The new program, described online July 20th in Vaccine, uses a combination of monovalent and hexavalent vaccine instead of only monovalent vaccine. Children receive monovalent hepatitis B vaccine at birth and at one month, plus hexavalent vaccine, including a hepatitis B vaccine component, at three, five and 12 months.

In addition, the hepatitis B vaccinations from one month and onward that earlier were carried out at the pediatric out-patient clinics were moved to the well baby clinics, where all other childhood vaccinations were already performed.

In total, the new study focused on 380 babies born to 356 HBsAg positive mothers between 2004 and 2008. Twenty-two children were lost to follow-up; of the remainder, 329 (92%) completed serology at ages 13 to 18 months, with 99% showing protective anti-HBs levels.

"This new vaccination schedule using a combination of mono-and hexavalent hepatitis B vaccines results in a very good antibody response and protection against mother-to-child infection," the investigators concluded.

In his email, Dr. Fischler said a similar approach might be helpful in improving results in other countries, "at least in countries with a known low prevalence of chronic hepatitis B, for example North/West Europe."

Dr. Maya Gambarin-Gelwan of Memorial Sloan-Kettering Cancer Center in New York City, who has studied perinatal HBV transmission, told Reuters Health by email that the study is "interesting," with an impressive serologic follow-up.

But, said Dr. Gambarin-Gelwan, "I think results of the study would be more powerful, if the authors compared two programs directly to each other in a randomized controlled study rather than comparing results to the historical controls."

"While excellent successful completion of recommended post-exposure prophylaxis and a very good antibody response was achieved with this program, as the authors pointed out, we need to see the sustainability of protection with this new vaccination schedule, and this will require further investigation."